FDA approves an old drug for morning sickness

Princess Kate may not need it anymore, but the FDA has just approved a drug… (Matt Dunham )

The Food and Drug Administration on Monday approved a drug to treat the severe nausea and vomiting that some women experience during early pregnancy. The Canadian-made medication will be marketed as Diclegis. It is the only prescription medication approved for pregnant women experiencing "morning sickness" that does not go away with a bland diet of small meals that are low in fat.

Diclegis was once known and marketed in the United States as Bendectin and taken by as many as one in 10 pregnant women. But after 27 years on the market, a spate of lawsuits in the early 1980s linked the drug to birth defects. Facing the prospect of steep legal damages, the firm manufacturing Bendectin, Merrell Dow Pharmaceuticals, pulled it from the U.S. market.

In announcing its decision to approve the drug for the U.S. market, the FDA's center for drug evaluation and research said the active ingredients in Diclegis do not pose any increased risk to a fetus. The manufacturer studied the drug's safety and effectiveness in 261 women experiencing nausea and vomiting because of pregnancy -- all at least 18 years old and between weeks seven and 14 of pregnancy. Women taking it in clinical studies provided to the FDA experienced greater improvement in nausea and vomiting than did those taking a placebo pill, the FDA said.

Diclegis is a combination of the antihistamine doxylamine succinate and pyridoxine hydrochloride, otherwise known as Vitamin B6. Marketed now by Duchesnay Inc. of Quebec, Canada, it is to be taken on an empty stomach at bedtime. The recommended dose of two pills may be expanded to four pills daily if the lower dose does not control symptoms.

The medication does come with a risk of drowsiness or sleepiness that can be severe, which prompted the FDA to warn women taking the drug not to operate heavy machinery or to engage in activities that would require mental alertness.